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1. Operating System - Overview

 


Definition: An operating system is a program that acts as an interface between the user and the computer hardware and controls the execution of all kinds of programs.

Memory Management: Memory management refers to the management of Primary Memory or Main Memory. It keeps track of primary memory, i.e., what part of it is in use by whom, what parts are not in use. It allocates and de-allocates the memory when a process requests it to do so.

Processor Management: Processor Management keeps track of the processor and the status of a process. The program responsible for this task is known as a traffic controller. It is responsible for allocating and de-allocating the processor (CPU) to a process.

Device Management: An Operating System manages device communication via their respective drivers. Device Management keeps track of all devices. The program responsible for this task is known as the I/O Controller. It decides which process gets the device when and for how much time. It allocates and de-allocates the device in the most efficient way.

File Management: A file system is normally organized into directories for easy navigation and usage. These directories may contain files and other directions. File Management keeps track of information, location, uses, status, etc. The collective facilities are often known as a file system.

Security: By means of passwords and similar other techniques, it prevents unauthorized access to programs and data.

Error Detecting Aids: Production of dumps, traces, error messages, and other debugging and error detecting aids.

Job Accounting: Keeping track of time and resources used by various jobs and users.

 

 

 


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